1. Field of the Invention
The present invention relates to the area of manufactured homes, and particularly to an augerable anchoring and stabilizing device for a manufactured home. In one aspect, the augerable ground anchor comprising a shaft, a helix affixed proximate one end of the shaft and a ground contact plate affixed at an opposing end of the shaft. The contact plate includes a first anchoring means for securing a side wall anchoring strap of the manufactured home to the ground anchor and a second anchoring means for anchoring a stabilizing strut from the manufactured home to the ground anchor. In another aspect, the invention is directed to an anchor assembly utilizing the augerable ground anchor and a stabilizing means movably affixed to the ground audio shaft. Yet another aspect of the invention is a method for stabilizing a manufactured home against wind movement.
2. Description of the Prior Art
Manufactured buildings, such as mobile homes, trailers, prefabricated houses, and the like are manufactured at a central manufacturing site. Upon completion, the buildings are moved to a location where they are to be occupied. Because these buildings are designed to be easily moved from the manufacturing site to the occupying location, they are built on a pair of parallel I-beam joists. The manufactured building is transported to and mounted upon vertical supports or piers, such as concrete masonry piers, prefabricated steel piers, or precast concrete jack stands located under the parallel joists of the main frame of the manufactured building, with the vertical supports being spaced longitudinally along the parallel joists at approximately eight (8) foot intervals.
It is important that the building also be anchored in position on the piers, so as to avoid the building being shifted off of the piers by strong winds or earth tremors. A building inadvertently shifted off of the piers can cause serious damage to the building and also can cause human injury.
Various types of stabilizing devices have been used to stabilize the manufactured buildings to keep the buildings from shifting off their piers in response to wind forces and earth movement. Non-limiting examples include guide wires, straps or other ties that connect the building to anchors or ground fixtures. One method for providing lateral wind displacement of manufactured buildings consists of using a plurality of tension straps and ground anchors to tether the manufactured home to the ground. In these systems, the tension straps typically extend downwardly from the support beams of the manufactured home frame to ground anchors that are deeply embedded into the soil. In one method, the tension straps are securely connected to the beams with strap connector assemblies that latch onto the support beams. Normally, a strap connector assembly comprises a metal clamp member that includes a hook that securely grips an upper flange of the support beam. The tension straps usually are threaded through a strap slot formed in the clamp member These strap slots normally arc configured so as to be parallel to the hook and the longitudinal direction of the manufactured home, such that the tension straps can be positioned substantially perpendicularly to the longitudinal direction of the manufactured home.
Typically, the ground anchor includes a shaft with one or more helical plates at the bottom of the shaft that is rotated or augered into the earth. An example of such an anchor is illustrated and described in U.S. Pat. No. 6,971,209 issued on Dec. 6, 2005 and assigned to Home Pride, Inc., the entire disclosure of which is incorporated herein by reference. Generally, such anchors have an elongated steel shaft with at least one helically shaped auger blade fixedly attached to the lower end of the shaft and an anchor head or drive head affixed at the upper end for positioning above the ground. The anchor or drive head includes at least one aperture or opening for inserting a split bolt. During installation, the anchor head is utilized as a drive attachment to drive the shaft and the helically shaped auger blade. The anchor shaft is rotated in a direction in which the auger blades penetrate the ground and forcibly drive the anchor shaft in a downward direction. The rotation of the anchor shaft is effected by attaching a driving means, such as an electric, gasoline, or hydraulic motor, to the head and turning the shaft, simultaneously applying a downward force on the anchor to drive the anchor to a predetermined depth in the ground.
An example of such an anchor system used to secure a manufactured home is disclosed in U.S. Pat. No. 6,343,449. As shown in FIG. 1, the manufactured home is supported by a frame that typically includes at least two parallel support steel I-beams 16 and a plurality of concrete block support piers 18 aligned along the lengths of the beams 16. The stabilizing system 12 includes a plurality of augerable ground anchors 13, each having an anchor or drive head 22 secured to the upper end of a shaft 23 which is further adapted for attaching a tension strap 26 to the anchor. As indicated in FIG. 1, the tension strap 26 can extend from the ground anchor upwardly about the outer periphery of the manufactured home or, in addition to or alternatively, a second tension strap 24 can connect to the support beams 16 of the manufactured home frame. The tensioned strap applies a downward force to the I-beams.
One issue with such an anchor system is that it does not provide sufficient resistance to longitudinal and lateral movement of the manufactured home during high wind gusts or during earth movement. Such anchors are typically installed vertically or even with a slight back angle just inside the perimeter of the home. The portion of the anchor that contacts the soil, i.e., the shaft and the anchor head, and used for fastening the tension strap has a relatively small surface area. Thus, when the anchor is pulled laterally by wind the upper end of the anchor presents only minimal resistance to the force and tends to bend toward the manufactured home, allowing the home to shift and a possible catastrophic loss of anchor stability.
Another issue with this type of anchoring system is that the tensioning strap received by openings in the anchor head generally have right angled edges, and consequently when a tension strap is bent around such an edge and tension is applied to the strap a sharp bend radius is produced in the tension strap. Tension straps are more likely to become fatigued and break at sharp radii bends than at bends with larger radii.
Yet another issue with such an anchor system is that there is a tendency for the steel anchor straps to break during considerable longitudinal movement of the manufactured home such as may be experienced in earthquakes and hurricanes. The failure of one or more of the anchor straps can then result in catastrophic failure of the support system as the home can become completely dislodged from the piers.
Another method for longitudinal and lateral stabilization of a manufactured home utilizes a system wherein the piers are set on top a pan having a means for attaching a substantially rigid member or brace that traverses a distance from the bottom of the pan to a location on one or both of the support I-beams. An example of such a system is shown in U.S. Pat. No. 4,261,149 which is typical of support systems using a foundation pad, pier, and longitudinal and lateral bracing struts which are secured between the manufactured home and the foundation pad.
Another example of such a system is disclosed in U.S. Pat. No. 6,318,032. As shown in FIG. 2, a manufactured home has a support I-beam 16 on the underside of the building. The I-beam extends the length of the building and is supported above the ground by an upright pier 18. The longitudinal stabilizing system includes a foundation pad 61, a joist connector 62, a plate connector 64, and a strut 68. The system may also be configured to utilize a second joist connector 62b, a second plate connector 64b, and a second strut 68b installed on the opposite side of the pier 18.
Another example of such a system is disclosed in U.S. Pat. No. 6,622,439. This anchoring system utilizes a foundation plate having a lower surface for contacting the ground, and an upper surface on which the pier is supported. Brace struts are connected between the chassis of the manufactured home and the foundation plates and extend both longitudinally and laterally.
An issue associated with such longitudinal and lateral stabilization systems is they are very cumbersome. When using non-concrete plates, anchoring of the plates into the ground is required before the pier is constructed and the braces are affixed to the pan. Thus, it is difficult or impossible to reposition the plates for alignment with the pier constructed. The plates have already been secured in the ground by anchors such as spikes or cleat walls. Moreover, when the metal foundation plate is stamped out and the edges are bent down to form walls, the walls are embedded in the soil to prevent the plate from shifting. While this type of plate is secured in shifting laterally and/or longitudinally, it is difficult to adjust the position of the plate once it has been embedded in the soil and the weight of the pier rests on the foundation plate.
Another issue with the aforementioned longitudinal and lateral stabilizing devices which utilize a pan system is that during high winds the lift exerted on manufactured home to shift it longitudinally and/or laterally from one or more piers is principally only the weight of the home itself The lift increases as wind speed increases. Thus, the force resisting lateral and longitudinal shift decreases which can result in catastrophic destruction of the home. Although anchors attached to the ground and sidewall anchor straps assist in preventing lift they do not prevent the lateral and longitudinal shift of the manufactured home frame from the piers.
Accordingly, it can be seen that there is still a need for an anchoring and longitudinal and lateral stabilizing device for use in anchoring and stabilizing a manufactured home or other mobile construct that would be easy to install, readily adjustable and provide significant resistance to lateral and longitudinal movement without the problems discussed above.